Wear is a complicated phenomenon caused by the relative movement of two contacting surfaces compressed together by a normal force. Prediction of the wear, in most cases, requires various experiments and microstructural characterization of the contacting surfaces. Mathematical models based on physical concepts could provide considerable help in understanding the physical behavior and hence the p...

Wear is a complicated phenomenon caused by the relative movement of two contacting surfaces compressed together by a normal force. Prediction of the wear, in most cases, requires various experiments and microstructural characterization of the contacting surfaces. Mathematical models based on physical concepts could provide considerable help in understanding the physical behavior and hence the p...

4. Plasma concentrations and urea entry rates were significantlj and linearly related. 5. The relationship between excretion rate and plasma urea concentration was best described by a cubic equation. 6. Degradation of urea in sheep was found to be extensive in all the animals studied ; as the protein intake increased, the quantity of urea degraded also increased but the percentage of ureaenteri...

BACKGROUND Diffusive clearance depends on blood and dialysate flow rates and the overall mass transfer area coefficient (K(o)A) of the dialyzer. Although K(o)A should be constant for a given dialyzer, urea K(o)A has been reported to vary with dialysate flow rate possibly because of improvements in flow distribution. This study examined the dependence of K(o)A for urea, phosphate and β(2)-microg...

T HE experiments presented here show that the rate of urea formation is accelerated in rats during the first 24 hours after removal of three quarters or all of the total renal tissue, and that the greater the amount of kidney excised the greater is the quantity of urea formed. The observations were made on rats in which urea formation from food protein was excluded by subsistence on a calorical...

Antidiuretic hormone leads to an increase in the permeability for water and urea in the inner medullary collecting duct. Hence, urea may not be an "effective" osmole in the inner medulla during maximal renal water conservation. Accordingly, the purpose of this study was to evaluate whether differences in the rate of urea excretion would influence maximum renal water conservation in humans. In w...

1. A 25% faecal suspension in sodium chloride solution, incubated anaerobically at 37 degrees C for 48 h, showed excellent survival of all the main groups of faecal bacteria. 2. All faecal incubation systems studied generated large amounts of ammonia, particularly those in which bacterial counts fell during incubation. As normal faeces contain negligible amounts of urea this ammonia must have b...

A simplified method for the determination of the rate of synthesis of albumin after the i. v. injection of C-carbonate is described. A number of experiments to check the accuracy of the CO2 measurements is reported. Good agreement is obtained between the specific activity of urinary urea, measured by means of our method and by the manometric method. Recoveries of 101.9 and 101.1% respectively a...

Forty ewes (3-6 years of age, average weight 41.2 kg)were randomly chosen from the flock of the sheep experiment station of Tripoli University. Ewes were divided into two groups, control group (C) received untreated barley straw and treatment group (T) received barley straw treated with 10% urea solution applied as 40% (V/W). Barley straw was sprayed with molasses when fed to animals. Both grou...